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Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Analyzing NMR shielding tensors calculated with two-component relativistic methods using spin-free localized
1Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260-3000, USA. jochena@buffalo.edu
The Journal of Chemical Physics
|May 2, 2008
Summary
This study extends a relativistic density functional theory method to analyze nuclear magnetic shielding tensors. The enhanced approach accurately calculates magnetic properties for various molecules, advancing computational chemistry.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Spectroscopy
Background:
- Nuclear Magnetic Resonance (NMR) spectroscopy is vital for molecular structure determination.
- Accurate calculation of NMR parameters like spin-spin coupling constants and shielding tensors is computationally challenging.
- Relativistic effects are significant for heavy elements and influence NMR properties.
Purpose of the Study:
- To extend a previously developed relativistic density functional theory (DFT) method for analyzing NMR spin-spin coupling constants.
- To incorporate gauge-including atomic orbitals (GIAO) for accurate treatment of magnetic field effects.
- To apply the extended method for analyzing nuclear magnetic shielding tensors in various chemical systems.
Main Methods:
- Utilized two-component (spin-orbit) relativistic DFT.
- Employed scalar relativistic natural localized molecular orbitals (NLMOs) and natural bond orbitals (NBOs).
- Included contributions from a field-dependent basis set (gauge-including atomic orbitals - GIAO).
Main Results:
- Successfully extended the analysis method to include NMR shielding tensors.
- Demonstrated the method's applicability to diverse molecules, including methane, plumbane, hydrogen iodide, tetrachloroplatinate(II), and hexachloroplatinate(IV).
- The spin-orbit NLMO/NBO approach provides a robust framework for calculating relativistic NMR properties.
Conclusions:
- The extended relativistic DFT method is effective for analyzing NMR shielding tensors.
- The inclusion of GIAO basis sets enhances the accuracy of magnetic property calculations.
- This work provides a valuable computational tool for studying NMR parameters, especially for systems with heavy elements.
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